Radio frequency identification (RFID) tags are electronic devices that can be affixed to items whose presence is to be detected and/or monitored. The presence of an RFID tag, and therefore the presence of the item to which the tag is affixed, can be interrogated and monitored wirelessly by devices known as RFID readers. Readers typically have one or more antennas transmitting radio frequency signals to which tags respond.
Efficient communication between tags and readers has become a key enabler in supply chain management, especially in manufacturing, shipping, and retail industries.
One need that has arisen in the context of supply chain management is a desire to have knowledge of tag movement within a coverage area (e.g., the area within which the reader can receive signals transmitted from tags).
Such detection can be important for accurate inventory counting as well as security applications by determining whether an item is entering or leaving an area.
Accordingly, there is a need for effective RFID tag detection.